DifficultyEasy

Time15–25 minutes

What you saveMica sheet $5–$20 DIY vs $80–$250 professionally

⚠️ BEFORE YOU START

Cavity-level work only, with the microwave unplugged. Never remove the outer metal cabinet of a microwave. The high-voltage capacitor inside stores a charge that can kill you, and it holds that charge after the unit is unplugged. Every step in this guide stays outside the cabinet or inside the cooking cavity — if a repair needs the case off, it is a job for a technician. Do not run the microwave with the cover removed — splatter will reach the waveguide and damage the magnetron.

Tools

Scissors or craft knife
Small screwdriver
Pencil
Fine sandpaper (optional)

Parts

Universal mica waveguide sheet $5–$15, or a model-specific cover $10–$30

Step by step

1 Unplug the microwave

Then open the door and let any heat out.
2 Photograph the old cover in place

Orientation matters, and the screw positions are easier to copy than to remember.
3 Remove the old cover

Undo the one or two small screws, or release the tabs from their slot. Some covers slide sideways rather than pulling straight off — do not force it.
4 Trace the shape onto the new sheet

Lay the old cover on the mica sheet and draw round it with a pencil, marking the screw holes and any notches.
5 Cut and finish the new cover

Cut just outside the line with scissors or a craft knife. Mica cuts cleanly but flakes at the edge — a light pass with fine sandpaper tidies it. Punch or drill the screw holes rather than tearing them.
6 Test fit before fixing

Offer it up and check it covers the opening completely with no gap at any edge. Trim if needed.
7 Fit it and test

Screw or clip it in, plug back in, and run a cup of water for a minute. Watch through the door — no flashes, and hot water at the end, means the job is done.

🔧 Hand-off point: If the new cover chars again within weeks, something behind it is wrong. Repeatedly replacing burned covers masks a magnetron or waveguide fault that needs a technician. find a microwave repair pro near you →

🔧 WHEN TO CALL A PRO

If a fresh cover chars again quickly, something else is wrong — usually a magnetron antenna problem or damage inside the waveguide. Repeated burning of new covers is a stop-and-call-someone symptom, not a consumable to keep replacing. If you'd rather skip it entirely, find a microwave repair pro near you →

Sources

Where the safety, regulatory and warranty claims on this page come from. Repair costs are our own figures based on Arizona market rates and OEM parts pricing.

Microwave Ovens — Radiation-Emitting Products U.S. Food & Drug Administration The federal requirement for two independent door interlocks plus a monitoring system, and the 21 CFR 1030.10 leakage limit — why an interlock must never be bypassed.